Findings & Prognosis for Refeeding Syndrome in Cats

Janine M. Calabro, DVM, DACVECC, Friendship Hospital for Animals, Washington, D.C.

ArticleLast Updated May 20222 min read

In the literature

Cook S, Whitby E, Elias N, Hall G, Chan DL. Retrospective evaluation of refeeding syndrome in cats: 11 cases (2013-2019). J Feline Med Surg. 2021;23(10):883-891.


The Research ...

Refeeding syndrome in cats is a complex condition characterized by multiple metabolic derangements (including hypophosphatemia, hypokalemia, and hypomagnesemia) that develops after reintroduction of nutrition following prolonged starvation or malnourishment.

This study used medical records from 4 referral hospitals to describe clinicopathologic findings, management, and outcome in 11 cats that developed refeeding syndrome after having been missing. Inclusion criteria included presence of a refeeding syndrome risk factor (eg, emaciation or severe weight loss following presumed starvation); hypophosphatemia or a maximum drop in phosphorous of ≥30% after refeeding; hypokalemia, hypoglycemia, and/or hyperglycemia; and treatment based on clinical diagnosis of refeeding syndrome. Data on clinicopathologic findings, blood product administration, nutritional plans, evidence of organ dysfunction, length of hospitalization, and outcomes were collected.

Cats had been missing for a median of 6 weeks (range, 3-104 weeks; n = 11), and mean percentage weight loss was 46% ± 7% (n = 8). Hypokalemia, hypoglycemia, hyperglycemia, and elevations in bilirubin and ALT were common. Organ and cardiovascular dysfunctions were documented in all cats; hypotension was noted in 6 cats. GI dysfunction, most often inappetence after initial feeding, developed in all cats. New or progressive neurologic deficits after refeeding were seen in 8 cats. All cats developed anemia, with 7 cats requiring transfusion therapy, and 6 cats developed acute kidney injury (AKI). All cats ate initially after presentation, and 4 cats ate voluntarily throughout hospitalization.

Eight cats survived to discharge; 1 cat died, and 2 cats were euthanized. Surviving cats were hospitalized for a mean of 14 ± 4 days. Maximum bilirubin concentration was significantly higher in nonsurvivors, and AKI was significantly associated with nonsurvival. ALT concentration and magnitude of decrease in phosphorous were not associated with outcome.

... The Takeaways

Key pearls to put into practice:

  • Refeeding syndrome is an uncommon clinical condition that may develop following realimentation after prolonged starvation or malnutrition. A variety of clinicopathologic changes are possible, but  hypophosphatemia, hypokalemia, and altered glucose homeostasis are most common in cats.

  • Cardiovascular, neurologic, and GI dysfunction may be common in cats with refeeding syndrome, and patients may develop anemia that requires transfusion therapy. Increased bilirubin and AKI appear to be associated with nonsurvival.

  • Good prognosis is possible, but prolonged and intensive care may be required.